The present invention relates to an angle adjusting device for adjusting an angle of inclination of a device such as a laptop type word processor, a personal computer and various lid shaped components to be mounted movably on a main body.
It is necessary for display component to be adjusted to an adequate angular position which is adequate for operator. Therefore, the angle of inclination has been adjusted without step by using various angle adjusting devices. As disclosed by the Japanese Patent Application Laid-open No. 63-23407 and Japanese Utility Model Application Publication No. 1-135397, the conventional angle adjusting devices have a rotatable axis directly or indirectly mounted on a component necessitating an angle adjustment such as display unit, a fixed axis mounted directly or indirectly on a main body and and a coil spring closely inserted over the rotatable axis and fixed axes for locking the rotation of the rotatable axis so as to surround. The display unit can be kept at an arbitrary angular position by means of frictional torque between the rotatable axis and the coil spring, and the rotatable axis can be rotated when an outer force stronger than the frictional torque is applied.
In conventional angle adjusting devices for a display device, a locking torque is obtained by a coil spring when the rotatable axis is rotated to the direction for reducing the coil diameter. When the rotatable axis is rotated to the reverse direction, the coil diameter is enlarged and occurs a slippage (slipping torque).
However, since the conventional angle adjusting devices have only one coil spring for locking operation, only the locking torque or the slipping torque can be obtained in accordance with the turning direction of the rotatable axis. Further feature can not be obtained.
In other words, it is impossible to obtain such feature having a large difference between the locking torque and the slipping torque or to obtain an arbitrary feature in the range of the slipping torque and the locking torque by using the conventional angle adjusting devices.
The present invention was developed considering the above situation and provides an angle adjusting device, which permits an arbitrary feature in designing by using a plurality of set spring.